3. Chiton. Six species.
This genus was so called from the resemblance of its testaceous covering to a coat of mail. The form of the Chiton is very similar to a well-known insect called the woodlouse, found in decayed timber; it generally adheres to rocks, or lies rolled up like a ball among seaweed and stones. In length it seldom exceeds an inch, except in tropical climates, where they are sometimes three or four inches long. In general there are eight valves, the termination of which is surrounded by a scaly or rough ligament, which enables the animal to expand or contract its shell freely. It presents a great variety of colour; in general it is dark brown, overcast with a shade of green, but some are beautifully variegated with pink, yellow, blue, or red; interior green or whitish.
Shell more or less elongated, consisting of a longitudinal series of eight very symmetrical calcareous pieces, more or less curved, and round at both extremities; summit more or less marked, and when imbricated, always from front to rear.
Chiton gigas.
C. squamosus.
C. Peruvianus.
C. spinosus.
C. fascicularis.
C. marginatus.
C. squamosus. The scaly Chiton. Pl. [1], fig. 1.